Try looking for the Microsoft TZedit.exe utility. It is not installed with the OS, but is an extended utility you can find on an OS disk (or used to).. There are some exe copies posted around the internet (disclaimers …). It allows view/edit of the time zones.
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones\E. South America Standard Time

I did a quick search for MS patch, but didn’t see any.
Good luck,
Charlie

From: firebird-support@yahoogroups.com <firebird-support@yahoogroups.com>
Sent: Monday, November 5, 2018 09:55
To: firebird-support@yahoogroups.com
Subject: [firebird-support] Firebird 3 and DST on Windowsw Server 2012



Down here in Brazil DST started that Sunday at 0:00. This year, DST was
postponed
due to general elections. To my surprise, today I observed that
CURRENT_TIMESTAMP
is returning a value 1 hour early than local time.

It only affects Firebird 3 running on Windows. For Firebird 2.5 and
Firebird 3 on Linux
everything looks ok.

Has anyone observed such behavior before? Is there a circumvent?

Ivan Cruz



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